G-Thiopentone1 gm/vial

G-Thiopentone is an ultra-short-acting barbiturate used strictly as an anesthetic/critical-care agent, administered only by personnel trained in anesthesia and airway management. Its uses can be classified by the strength of supporting evidence as follows:

Established / FDA-Approved Uses

• Induction of general anesthesia, typically as the sole agent for brief procedures or as the induction agent before maintenance with other anesthetics.
• Supplementation of regional anesthesia to produce sedation or light general anesthesia during regional/local anesthetic techniques.
• Component of balanced anesthesia, used together with other anesthetic, analgesic, and neuromuscular-blocking agents as part of a combination anesthetic technique.

Specialist/ICU-Directed Uses

• Control of convulsive states, including status epilepticus, when used under specialist or intensive-care supervision, generally after first-line anticonvulsants have failed.
• Reduction of elevated intracranial pressure in specific neurocritical care contexts (so-called "barbiturate coma"), directed by a specialist/ICU team with continuous monitoring.

G-Thiopentone is not intended for outpatient, self-administered, or non-specialist use under any circumstance; it must be given only where resuscitation and airway equipment and personnel trained in their use are immediately available.

Thiopental Sodium is supplied as a sterile powder for injection containing the generic active ingredient Thiopental Sodium (a sulfur-containing barbiturate salt), typically combined with anhydrous sodium carbonate to maintain solution alkalinity and stability after reconstitution. It is available in single-dose or multiple-dose vials in various strengths (e.g., 500 mg, 1 g, 2.5 g, or 5 g of Thiopental Sodium per vial) intended for intravenous use only after reconstitution with an appropriate diluent. Exact strength and pack size vary by manufacturer; always confirm the label of the specific product being used.

G-Thiopentone is an ultra-short-acting barbiturate anesthetic belonging to the thiobarbiturate subclass. It is supplied as a pale yellow-white, hygroscopic powder that is reconstituted with a compatible diluent (such as sterile water for injection, 0.9% sodium chloride, or 5% dextrose) to form a solution for intravenous injection or infusion.

Because of its high lipid solubility, G-Thiopentone crosses the blood-brain barrier extremely rapidly, producing loss of consciousness within seconds of intravenous administration. Its clinical effect is very brief after a single dose because the drug redistributes from the brain into muscle and fat rather than being eliminated, which is why it is used almost exclusively for anesthesia induction and short procedures rather than for maintenance anesthesia or long-term sedation.

G-Thiopentone is a Schedule III controlled substance in many jurisdictions and is intended strictly for use by, or under the direct supervision of, personnel qualified in the administration of general anesthesia and the management of the airway and cardiovascular emergencies.

G-Thiopentone belongs to the therapeutic class of barbiturates, specifically the ultra-short-acting thiobarbiturate general anesthetics, used for induction of anesthesia and, in specialist/ICU settings, for control of seizures and reduction of intracranial pressure.

Thiopental Sodium is a CNS depressant that acts primarily by enhancing the inhibitory effect of gamma-aminobutyric acid (GABA) at the GABA-A receptor. It binds to a distinct barbiturate site on the GABA-A receptor-chloride ionophore complex, increasing the duration of chloride channel opening (in contrast to benzodiazepines, which increase the frequency of channel opening). At higher concentrations, Thiopental Sodium can also directly activate chloride channels independent of GABA and can inhibit excitatory glutamate receptor activity, contributing to generalized CNS depression, unconsciousness, and, at sufficient doses, respiratory and cardiovascular depression.

Onset of action after an intravenous induction dose occurs within about 30-45 seconds because of the drug's very high lipid solubility and rapid delivery to the highly perfused brain. Recovery from a single dose is rapid (typically within 5-10 minutes) due to redistribution of the drug from the brain to less well-perfused tissues such as muscle and fat, not because of elimination. With repeated doses or continuous infusion, the drug accumulates in fat stores, which prolongs recovery time substantially (context-sensitive accumulation).

Thiopental Sodium is metabolized almost entirely in the liver, mainly by oxidative pathways, and its metabolites are excreted in the urine; only a small fraction is excreted unchanged. It has minimal analgesic effect at sub-anesthetic doses and can even lower pain threshold (anti-analgesic effect), which is why it is often combined with analgesic or other anesthetic agents in balanced anesthesia.

G-Thiopentone is for intravenous administration only, given as a slow bolus injection or as a dilute continuous infusion, strictly by, or under the direct supervision of, personnel trained in anesthesia and resuscitation.

• Confirm a secure, well-functioning intravenous line in a suitable vein before injection; do not attempt administration if suitable venous access cannot be obtained.
• Administer slowly and titrate to the desired clinical endpoint; rapid injection increases the risk of profound respiratory and cardiovascular depression.
• Avoid extravasation into surrounding tissue and avoid accidental intra-arterial injection, both of which can cause severe local tissue damage (see Precautions and Warnings).
• Have resuscitative equipment, supplemental oxygen, and endotracheal intubation equipment immediately available before administration, and continuously monitor airway, breathing, and cardiovascular status during and after use.
• Reconstituted solutions must be prepared and used according to the product's reconstitution instructions (see Reconstitution) and within the stated in-use stability period.

G-Thiopentone has clinically significant interactions with other agents that affect the central nervous system or that alter its metabolism/excretion:

• Other CNS depressants (opioids, benzodiazepines, other sedative-hypnotics, alcohol): additive respiratory depression, sedation, and cardiovascular depression; doses of G-Thiopentone and of concomitant CNS depressants must be reduced and carefully titrated when used together.
• Other general anesthetic and neuromuscular-blocking agents: G-Thiopentone is frequently used in combination with these as part of balanced anesthesia; the anesthesia team titrates each agent's dose according to protocol to avoid excessive combined depression.
• Opioid analgesics: G-Thiopentone has little or no analgesic effect and may reduce the pain threshold at subhypnotic doses; opioids are typically co-administered for analgesia, with attention to additive respiratory depression.
• Probenecid: can prolong and intensify the effect of G-Thiopentone by altering its distribution/elimination; reduced dosing may be required.
• Monoamine oxidase inhibitors (MAOIs): may exaggerate or unpredictably prolong the hypnotic/depressant effect of G-Thiopentone; use with caution.
• Antihypertensive agents (e.g., diazoxide) and other drugs that lower blood pressure: can increase the risk of pronounced hypotension when combined with G-Thiopentone.

The anesthesia/critical-care team should be informed of all other medicines, herbal products, and alcohol use before G-Thiopentone is administered.

G-Thiopentone is administered only in monitored anesthesia/critical-care settings; even so, it carries significant risks of dose-related adverse effects, including:

• Respiratory: respiratory depression, apnea, laryngospasm, and bronchospasm, particularly with rapid injection or in patients with reactive airway disease.
• Cardiovascular: hypotension and myocardial depression, especially in hypovolemic, elderly, or hemodynamically unstable patients; arrhythmias may occur.
• Neurological/recovery-related: prolonged somnolence or delayed recovery, particularly after repeated dosing or infusion due to drug accumulation in fat.
• Injection-site/vascular: pain, venous thrombosis, or tissue damage from extravasation; severe tissue necrosis, arteriospasm, and risk of gangrene if the drug is accidentally injected intra-arterially (a medical emergency requiring immediate specific management).
• Hypersensitivity: rash, and rarely anaphylactoid or anaphylactic reactions.
• Rare: hemolytic anemia and peripheral nerve palsy (usually related to positioning during prolonged unconsciousness) have been reported.

G-Thiopentone crosses the placenta rapidly. It is used, when clinically indicated, for induction of general anesthesia in pregnant patients requiring surgery (including cesarean section), under the direct supervision of an anesthesia specialist who will weigh maternal and fetal considerations, select the dose, and manage timing relative to delivery, since transplacental transfer can cause transient neonatal respiratory depression/sedation if delivery occurs soon after administration. Such use should be limited to situations where anesthesia is clearly needed and should always be directed by a qualified anesthesia provider as part of the overall obstetric/surgical plan.

Small amounts of G-Thiopentone may appear in breast milk following administration, particularly after larger or repeated doses. Breastfeeding mothers who require anesthesia with G-Thiopentone should follow their physician's guidance on breastfeeding timing after the procedure, generally allowing time for the drug to clear before resuming breastfeeding.

The following precautions apply to the use of G-Thiopentone:

• Specialist administration only: G-Thiopentone must be given only by, or under the direct supervision of, personnel trained in general anesthesia and airway management, with resuscitation equipment, oxygen, and endotracheal intubation equipment immediately available, because of the risk of respiratory depression, apnea, laryngospasm, and cardiovascular depression (hypotension, myocardial depression). It is not intended for use outside such a supervised setting.
• Extravasation and intra-arterial injection: G-Thiopentone is highly alkaline and irritant to tissue; extravasation can cause local tissue damage and necrosis, and accidental intra-arterial injection can cause severe pain, arteriospasm, thrombosis, and tissue necrosis/gangrene. Secure, confirmed intravenous access must be established before injection, and any suspected extravasation or intra-arterial injection requires immediate specific management by the treating team.
• Cardiovascular and respiratory disease: use with particular caution in patients with cardiovascular instability, hypotension, severe cardiac disease, or reactive airway disease/asthma (short of status asthmaticus, which is a contraindication - see Contraindications), as G-Thiopentone can worsen hypotension and provoke bronchospasm.
• Hepatic or renal impairment: use with caution and reduced dosing, since hepatic metabolism is required for elimination and drug effect may be prolonged.
• Myasthenia gravis and other neuromuscular conditions: increased sensitivity to the respiratory-depressant effects of G-Thiopentone may occur; use with caution and appropriate monitoring.
• Prior porphyria or absence of suitable IV access: these are absolute contraindications - see Contraindications.
• Accumulation with repeated dosing: repeated boluses or prolonged infusion lead to accumulation in fat and markedly prolonged recovery time; total cumulative dose and recovery must be monitored, especially in prolonged procedures or ICU use.

Overdose or excessive dosing of G-Thiopentone can cause profound central nervous system, respiratory, and cardiovascular depression, including deep unconsciousness, apnea, severe hypotension, and cardiovascular collapse; because G-Thiopentone is given only in monitored settings, overdose is typically recognized and managed immediately by the treating anesthesia/critical-care team. If overdose or an adverse cardiorespiratory event is suspected, immediate medical attention, airway support, and emergency resuscitative measures must be provided without delay; there is no specific antidote, and management is entirely supportive, including airway protection, mechanical ventilation, oxygen, and circulatory support as needed until the drug's effects resolve.

Store the unreconstituted powder for injection at room temperature (below 30°C), protected from light and moisture, and keep out of reach of children. After reconstitution, the solution has limited stability and must be used promptly (per the product's labeling, generally within 24 hours of preparation, and stored appropriately during that period); discard any unused reconstituted solution.

Hepatic impairment: since G-Thiopentone is primarily metabolized in the liver, patients with significant hepatic impairment may show prolonged and intensified effects; reduced dosing and careful titration by the anesthesia/critical-care team are required (see Precautions and Warnings).

Renal impairment: use with caution and reduced dosing, as elimination of metabolites depends on renal function.

Elderly or debilitated patients: require reduced doses and slower titration due to increased sensitivity, slower redistribution/metabolism, and greater risk of hypotension and prolonged recovery.

Cardiovascular instability/hypovolemia: increased risk of profound hypotension; dose reduction and careful titration are needed.

Pediatric use: see Pediatric Uses.

G-Thiopentone is used for the shortest duration necessary to achieve the clinical goal: typically a single induction dose lasting minutes for anesthesia induction, intermittent or infusion dosing limited to the duration of the surgical procedure for maintenance anesthesia, or a specialist/ICU-directed course (hours to days, with continuous monitoring) for status epilepticus or intracranial pressure control. It is not intended for repeated, intermittent, or outpatient use outside these monitored clinical contexts, and the treating specialist reassesses the need for continued administration throughout its use.

G-Thiopentone powder for injection must be reconstituted before use, strictly according to the manufacturer's instructions for the specific product and strength. It is typically reconstituted with sterile water for injection, 0.9% sodium chloride injection, or 5% dextrose injection to produce a solution of the required concentration (commonly around 2-2.5% for bolus induction use, further diluted for continuous infusion, per institutional/anesthesia protocol). The reconstituted solution should be inspected visually for particulate matter and discoloration before use, and any solution that is not clear or shows precipitation should be discarded. Reconstituted solutions have limited stability and must be used within the timeframe specified in the product labeling (commonly within 24 hours when stored appropriately); unused reconstituted solution should be discarded after this period.

Barbiturates; ultra-short-acting thiobarbiturate general anesthetics

Thiopental Sodium produces general anesthesia by potentiating inhibitory GABA-A receptor-mediated chloride ion influx in the central nervous system, prolonging the opening of the chloride channel and thereby increasing neuronal inhibition. At higher concentrations it can also directly activate the chloride channel independent of GABA and suppress excitatory glutamatergic transmission. Because of its high lipid solubility, Thiopental Sodium rapidly enters the highly perfused brain to produce loss of consciousness within seconds, and the anesthetic effect of a single dose terminates quickly through redistribution of the drug away from the brain into muscle and fat, rather than through metabolism or excretion.

Category C

G-Thiopentone may be used by an anesthesia specialist for induction of general anesthesia in children, with dosing individualized on a weight (mg/kg) basis; pediatric patients may require different per-kilogram dosing than adults, and only clinicians experienced in pediatric anesthesia should administer it. Use in neonates and very young infants requires particular caution given their immature hepatic metabolism and greater sensitivity to respiratory and cardiovascular depression. Formal safety and efficacy data in certain pediatric subgroups (e.g., neonates, patients with specific comorbidities) may be limited, and G-Thiopentone should be used in children only when clearly indicated and under continuous specialist monitoring, never outside a supervised anesthesia/critical-care setting.